Low-voltage surgical cast cutter with vacuum exhaust of debris

ABSTRACT

A surgical cast cutter or other power tool comprises a main tool section and a complementary hose section releasably secured to the tool section rearwardly thereof. The sections have respective cooperating rib means formed therein which slidably engage each other (in a direction transverse to the longitudinal axis of the tool section) as the sections are brought together; and the sections are retained by a releasable latching means. A low-voltage electric motor in the tool section drives a transmission which oscillates a cutter mounted forwardly of the tool section. A debris conduit in the tool section communicates with an opening formed in the hose section when the sections are joined together. The hose section carries a flexible vacuum hose communicating with the opening therein, thereby facilitating removal of dust particles generated during operation of the cutter to remove a plaster cast. A low-voltage cable is carried by the vacuum hose and is connected to electrical contacts carried by the hose section. These contacts engage corresponding electrical contacts carried by the tool section, when the sections are brought together, for energization of the motor through a switch carried by one of the sections. The sections have respective side housing edges which are inclined with respect to the respective cooperating rib means; these side housing edges are brought into substantial abutting engagement when the sections are fully joined. The opening in the hose section, as well as the rearward opening of the debris conduit, are also inclined with respect to the respective cooperating rib means to assure good sealing engagement therebetween when the sections are fully joined.

BACKGROUND OF THE INVENTION

Surgical cast cutters have been employed for many years. These tools areportable and have a small circular saw blade or cutter that oscillatesthrough a limited angle, thereby assuring that the patient will not beinjured while the cast is being removed. The oscillating cutter isdriven by a suitable transmission, which may include a bifurcated fork,and the transmission is driven by an electric motor housed in the tool.The motor is usually an a.c. motor supplied by line voltage.

Because of the dust and debris generated by the cutter during removableof the plaster cast, the prior art (as exemplified by U.S. Pat. Nos.3,103,069 and 3,481,036) has resorted to a built-in impeller or fan forgenerating a vacuum exhaust. The fan is driven directly by the rear endof the motor shaft and communicates with one end of a debris conduit orchannel suitably formed in the housing to one side of the motor. Theother end of the conduit terminates forwardly of the tool housing andadjacent to the cutter. As a result, the dust and debris are withdrawnfrom the vicinity of the cutter and are deposited laterally of the fanin a receptable carried by the tool.

Another prior art teaching of a surgical cast remover with a vacuumexhaust of the dust particles is U.S. Pat. No. 2,232,733, wherein thecutter is driven by a flexible power shaft, and wherein the vacuum hoseis disposed substantially parallel to the flexible power shaft andterminates in a dust bag remote from the cutter. Moreover, in thegeneral art relating to portable electric tools and appliances, it iswell known to attach a vacuum hose to the housing of the tool forremoval of the dust, debris or other particles generated duringoperation of the tool, and to connect the hose to a conventional vacuumcleaner located remotely from the tool; such an arrangement isexemplified by U.S. Pat. No. 2,929,177.

While these prior art designs and structural arrangements of surgicalcast cutters and the like may be somewhat adequate for the purposesintended, nevertheless, there are a number of inherent disadvantages ordeficiencies associated therewith, the more significant of which may beenumerated as follows: (1) the overall tool is relatively heavy andbulky, hence somewhat cumbersome, awkward and inconvenient to use; (2)the motor is operated from line voltage, which requires suitableinsulation to maintain electrical safety requirements; (3) the a.c.motor is fairly large and runs at a relatively high speed, therebyincreasing the ambient vibration levels, and as a result, any prolongedusage of the tool may become somewhat uncomfortable and tiring; (4) themotor-driven exhaust fan generates relatively high noise levels, whichcan become irritating in the usually serene atmosphere of a clinic orhospital. (5) the cost of original manufacture and assembly, as well asthe cost of subsequent service and repair, are relatively expensive; and(6) the designs concentrate on a single-purpose tool, hence arerelatively inflexible, and are not really adaptable to a broad line ofrelated products for medical and other purposes.

SUMMARY OF THE INVENTION

Accordingly, it is an object of the present invention to alleviate thedeficiencies of the prior art by providing a substantially improvedsurgical cast cutter.

It is another object of the present invention to provide a surgical castcutter which comprises a main tool section and a complementary hosesection removably secured rearwardly thereof, the hose section carryinga flexible hose extending rearwardly thereof and leading to aconventional vacuum cleaner remote from the portable cast cutter.

It is yet another object of the present invention to provide a surgicalcast cutter having a housing with a low-voltage electric motor therein,the motor being energized by a low-voltage cable carried by the flexiblevacuum hose; and wherein electrical contacts carried by the hose section(and connected to the cable) engage corresponding electrical contactscarried by the tool section, when the sections are brought together.

It is again yet another object of the present invention to providerespective rib means, one on the tool section and the other on the hosesection, the rib means being complementary to each other and beingformed substantially at right angles with respect to the longitudinalaxis of the tool; and wherein the respective side housing edges of thesections are inclined at an acute angle with respect to thecomplementary rib means, whereby, when the mating sections are broughttogether in a direction substantially at right angles to thelongitudinal axis of the tool, the complementary rib means slidablyengage each other to guide the respective inclined side housing edgesinto substantial abutting engagement, when the sections are fully joinedtogether.

It is a further object of the present invention to provide a rearwardopening on the tool section that communicates with a forward opening onthe hose section, when the sections are fully joined together, foregress of the dust particles through the rearwardly-extending vacuumhose; and wherein the respective openings are inclined with respect tothe complementary guiding rib means on the respective sections, whereby,when the sections are brought together in a direction parallel to theplane of the complementary rib means, the openings become alined withrespect to each other with limited wear on the adjacent surfaces andwith substantially no air leakage therebetween.

It is a still further object of the present invention to provide asurgical cast cutter which is relatively lightweight, convenient andeasy to use, and has relatively low vibration and noise loads associatedtherewith.

It is a yet still further object of the present invention to provide asurgical cast cutter which has an inherently low-voltage operation,thereby obviating the necessity for rigid electrical insulationrequirements.

It is again a yet still further object of the present invention toprovide a surgical cast cutter which is more economical to produce andto service, yet has design flexibility for facilitating the marketing ofa board line of related products for medical and other uses.

These and other objects of the present invention will become apparentfrom a reading of the following specification, taken in conjunction withthe enclosed drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevation of the improved surgical cast cutter of thepresent invention, with its remote power supply and vacuum cleaner beingshown somewhat schematically,

FIG. 2 is an exploded elevation of the mating sections of the surgicalcast cutter, drawn to an enlarged scale, and with certain parts brokenaway and sectioned;

FIG. 3 is a rear elevation of the main tool section, taken along thelines 3--3 of FIG. 2, and drawn to an enlarged scale;

FIG. 4 is a front elevation of the mating hose section, taken along thelines 4--4 of FIG. 3, and drawn to an enlarged scale;

FIG. 5 is a side elevation of respective portions of the mating sectionsin their fully engaged position, and with parts broken away andsectioned;

FIG. 6 is a detail section view, taken along the lines 6--6 of FIG. 5,and showing the cooperating rib means which slidably engage each otherfor progressively bringing the mating sections together;

FIG. 7 is a view taken along the lines 7--7 of FIG. 5, showing theswitch for energizing the motor, and further showing the screw forselectively disabling the releasable latch and precluding an inadvertentoperation thereof; and

FIG. 8 is a schematic wiring diagram, showing the high-voltageconnection to the vacuum cleaner, and further showing the low-voltage(12 volt) supply to the cast cutter.

DESCRIPTION OF THE PREFERRED EMBODIMENT

With reference to FIG. 1, there is illustrated a surgical cast cutter 10with which the teachings of the present invention may find moreparticular utility. However, it will be appreciated by those skilled inthe art that the teachings of the present invention are equallyapplicable to other power tools intended for medical or other purposes,especially wherein similar environmental characteristics or problems areencountered. With this in mind, the surgical cast cutter 10 generallycomprises a main tool section 11 formed along a generally longitudinalaxis, a generally axially-disposed mating hose section 12 releasablysecured to the tool section rearwardly thereof, an oscillating blade orcutter 13 mounted forwardly of the tool section, a combination guard andhood 14 for the cutter, a switch 15 for energizing the unit, a flexiblevacuum hose 16 carried by the hose section and extending rearwardlytherefrom, a remote vacuum cleaner 17 on the other end of the hose, anda power supply 18.

With reference to FIG. 2, the tool section 11 has a housing 19 with alow voltage (12 volt) motor 20 therein. The motor drives a transmission21, including a bifurcated fork 22, which is connected to a longitudinalshaft 23 mounted in the housing for limited oscillation therein. It willbe appreciated that the transmission, bifurcated fork, oscillating shaftand cutter are all conventional, form no part of the present invention,and hence have been shown somewhat schematically herein; conversely, thescope of the present invention is not to be limited thereby. With thisin mind, the cutter (which preferably is circular in plan outline) ismounted on the end of the shaft and is retained thereon by an internallythreaded knob 24, the outer surface of which preferably haslongitudinally serrations or knurls for facilitating a convenientmanipulation. A debris conduit 25 is formed within the housing,preferably above the motor and isolated therefrom. The debris conduitcommences in an opening 26 forwardly of the tool; this opening is withinthe hood and in the vicinity of the oscillating cutter for removal ofthe dust particles and other debris therefrom. The other end of theconduit terminates in an opening 27 formed rearwardly of the housing forthe tool section.

With reference again to FIG. 2, and with further reference to FIGS. 3through 6, the housing for the tool section comprises a pair ofcomplementary mating halves 19a and 19b joined together along a commonlongitudinal midplane (as shown more clearly in FIG. 3). These matinghalves of the housing are preferably injection molded from a suitableplastic material having good structural rigidity and relatively highimpact strength. The rear portion of the tool section housing 19 isformed with rib means which preferably comprises a pair of spacedparallel ribs 28 integrally formed on the respective housing halves in adirection which is transverse to (and preferably, substantially at rightangles to) the generally longitudinal axis of the tool section). Asshown more clearly in FIG. 4, the complementary hose section 12 hascorresponding ribs means which preferably comprises a pair of spacedparallel ribs 29 integrally formed thereon.

When the respective tool sections 11 and 12 are brought together, asshown in FIGS. 5 and 6, the corresponding respective rib means slidablymesh or engage each other (progressively relative to one another) toassure that the respective tool sections will be brought together in adirection which is transverse to (and substantially at right angles to)the generally longitudinal axis or arrangement of the overall tool.

When the sections are brought together, the debris opening 27 in thetool section communicates with an opening 30 formed in the hose section.As shown in FIG. 2, these debris openings 27 and 30 are each inclined atan acute angle with respect to the corresponding rib means in the toolsection and hose section, respectively. Thus, as the respective sectionsare brought together, their respective openings 27 and 30 are broughtprogressively into a complete alinement with substantially no airleakage therebetween at the adjacent mating surfaces of the respectivesections. Otherwise, if the openings were not so inclined, but wereformed perpendicular to the longitudinal axis of the tool and parallelto the direction of mating engagement of the respective sections, wearand possibly some deformation may occur on the adjacent surfacesresulting in substantial air leakage between the alined openings. As aconsequence thereof, the efficiency of the vacuum dust exhaust wouldbecome diminished, and the electrical components of the tool(hereinafter described) would possibly deteriorate because of dustaccumulation and resultant contamination.

The surgical cast cutter is energized by a low-voltage cable 31 carriedwithin the flexible vacuum hose (or otherwise formed therein). The useof a low-voltage cable means, aside from surgical cast cutters or thelike, is generally known in the art (as exemplified by U.S. Pat. No.2,958,894). The cable is connected through the switch 15 and suitableconductors to a pair of spaced electrical contacts 32. The conductors,being conventional, have been shown somewhat schematically (as at 32aand 32b) for ease of illustration. The respective contacts 32 projectforwardly of the hose section 12 (as shown in FIGS. 2 and 4) and, whenthe sections are brought together, engage a corresponding pair ofelectrical contacts 33 carried by the tool section 11 and projectingrearwardly therefrom. The contacts 33 on the tool section are connectedto the low-voltage motor by suitable conductors; these conductors arealso conventional and hence have been shown somewhat schematically (asat 33a and 33b) for ease of illustration. The switch is preferably ofthe toggle type and is recessed within a rectangular projecting boss 34molded integrally with the hose section (as shown in FIGS. 2 and 7).

When the switch 15 is moved into its "on" position to energize themotor, the cutter 13 is oscillated through a small acute angle (ofapproximately seven (7) degrees in a preferred embodiment) through theconventional driving transmission means. As shown by the small arrows inFIG. 2, the dust particles and other debris generated by the cutterduring operation of the tool (to remove a plaster cast or the like) aredrawn through the hood 14, forward opening 26 in the tool section 11,debris conduit 25, rearward opening 27, alined opening 30 in the hosesection 12, and the flexible hose 16 to the vacuum cleaner 17.

Because of the combination of the low-voltage operation of the motor,together with the vacuum exhaust of the dust particles through aflexible hose projecting rearwardly of the tool and connected to aremote vacuum cleaner, the deficiencies of the prior art aresubstantially alleviated if not avoided altogether, and the advantageand benefits of the present invention are thus obtained. In partialsummary, these advantages are as follows: lightweight, improvedportability for convenient usage, efficient removal of the dustparticles and other debris, and reduced vibration and ambient noiselevels, all in a design that may be manufactured and serviced moreeconomically.

Releasable latching means are provided for maintaining the respectivemating sections in their fully joined position. With reference again toFIG. 5, this releasable latching means comprises a latch 35 carried bythe hose section, projecting forwardly therefrom, and biased forwardlyby a spring 36. The latch may be manually retracted within the hosesection (against the resilient bias force of the spring) by means of arelease button 37 formed integrally with the latch and projectingthrough an opening below the hose section, thereby facilitating removalof the hose section from the tool section. Conversely, when therespective sections are brought together (by means of the cooperatingrespective rib means as previously described) the latch engages a camledge 38 molded integrally with the tool section 11 and projectingrearwardly therefrom. The latch rides up over the stationary ledge and"snaps" into place to securely retain the mating sections together.Furthermore, the sections have respective adjacent side housing edges 39and 40 (as shown in FIGS. 2 and 5) which are inclined at an acute anglewith respect to the cooperating respective rib means. This assures thatas the sections are brought together, in the direction of the arrow 41(in FIG. 2) and substantially at right angles to the generallylongitudinal axis of the tool, that the respective inclined side housingedges 39 and 40 will not interfere with the desired sliding actionbetween the sections and will eventually be brought into substantialabutting engagement therebetween.

Aside from a surgical cast cutter or the like, the relative movementbetween a pair of mating housing sections (in a direction substantiallyperpendicular to the generally longitudinal axis of the tool) togetherwith the cooperating rib means, inclined respective housing edges,mating electrical contacts carried respectively by the sections, andreleasable latching means--are all generally known in the power toolfield (as evidenced by U.S. Pat. No. 3,973,179). However, it is theapplication of those concepts and structures to a surgical cast cutteror the like, and especially to a surgical cast cutter having alow-voltage operation and a vacuum hose projecting rearwardly therefromfor efficient collection of the dust particles by a remote vacuumcleaner, which is new and constitutes a substantial contribution to thisspecific and well-developed art.

Moreover, the surgical cast cutter of the present invention providesadditional structure, unique to its environment, which has not beendisclosed nor taught in the aforesaid U.S. Pat. No. 3,973,179. Morespecifically, means are provided for selectively disabling thereleasable latching means and precluding its inadvertent actuation oncethe mating sections are joined together. This means comprises a screw 42carried by a threaded opening 43 in the hose section and accessiblerearwardly thereof (below the switch as shown in FIGS. 2 and 7). Thisscrew may be driven into the hose section (by means of a smallscrewdriver blade or other suitable implement, and within the spring) tobear against the rear portion of the latch 35 and preclude the latchfrom being manually recessed into the hose section, regardless of anysubsequent attempted actuation of its integral release button 37. Thus,when the screw 42 is fully seated to disable and override the latch 35,an accidental jarring or attempted actuation of the release button 37will have no consequential effect; and the hose section 12 will remainjoined to the tool section 11, thereby precluding an inadvertentseparation of the mating sections during operation of the tool.Conversely, to enable the latch to again become operative, the screw iswithdrawn partially from its threaded recess (again by use of a suitableimplement) to enable the latch to be withdrawn sufficiently within thehose section to allow the mating sections to become separated.

In addition, the tool section 11 is provided with adownwardly-projecting arcuate transverse ridge 44 formed integrallythereon, and the hose section 12 is provided with anexternally-accessible arcuate transverse groove 45 formed thereon (asshown in FIGS. 2 and 5) to receive the ridge, when the sections arefully joined. The complementary interfitting ridge 44 and groove 45provide good structural rigidity and preclude axial separation of themating sections in a direction substantially parallel to thelongitudinal axis of the tool.

Finally, with reference again to FIG. 1 and with further reference toFIG. 8, the power supply 18 comprises the usual transformer 46 andbridge rectifier 47 for supplying 12 volt D.C. power to the surgicalcast cutter 10. The low-voltage cable 31 (carried by the flexible vacuumhose 16) is connected via cable 48 and plug 49 to a suitable receptacle50 on the power supply 18. The end of the flexible hose, as at 51, isreceived within a suitable coupling 52 on the vacuum cleaner 17. Thevacuum cleaner has a cable 53 terminating in a plug 54 received within areceptacle 55 on the power supply for supplying line voltage to thevacuum cleaner. The power supply has a cable 56 and plug 57 for plugginginto the line 58. As shown in FIG. 8, a main switch 59 and fuse 60 arealso provided.

Because of its modular "two section" construction, together with itslow-voltage operation and vacuum exhaust to a remote vacuum cleaner, theimproved surgical cast cutter of the present is also adaptable to abroad line of additional products for medical and other purposes,wherein similar operational and environmental characteristics may beencountered.

Obviously, many modifications may be made without departing from thebasic spirit of the present invention. Accordingly, it will beappreciated by those skilled in the art that within the scope of theappended claims, the invention may be practiced other than has beenspecifically described herein.

I claim:
 1. A surgical cast cutter, comprising a generally longitudinaltool section and a complementary hose section releasably secured to thetool section rearwardly thereof, first rib means formed transversely onthe rearward portion of the tool section, second rib means formedtransversely on the forward portion of the hose section and cooperatingwith the first rib means to slidably guide the sections into engagementwith each other, the sections have respective housing edges inclinedwith respect to the first and second rib means, the housing edgessubstantially abutting one another when the sections are fully joinedtogether, releasable latching means for retaining the sections together,electrical contact means carried by each of the sections andrespectively engaging each other when the sections are joined together,the tool section having a housing with an electric motor therein, firstconductor means connecting the motor to the respective contacts on thetool section, second conductor means connecting the respective contactson the hose section to a source of power, an oscillating cutter mountedforwardly of the housing, a driving transmission means between the motorand the cutter, switch means for selectively energizing the motor, thehousing having a debris conduit formed therein, the conduit commencingnear the cutter and terminating in rearward opening in the tool sectionhousing, the hose section having a forward opening formed therein andcommunicating with the rearward opening in the housing when the sectionsare joined together, means for substantially sealing the sectionsagainst air leakage therebetween adjacent to the communicating openings,and a vacuum hose carried by the hose portion, communicating with theopening therein, and extending rearwardly therefrom.
 2. A surgical castcutter, comprising a tool section and a complementary hose sectionreleasably secured to the tool section, cooperating means for manuallysliding the sections relative to one another, releasable latching meansfor retaining the sections together, means for selectively disabling thelatching means to prevent the sections from being separatedinadvertently, electrical contact means carried by each of the sectionsand respectively engaging each other when the sections are joinedtogether, the tool section having a housing with an electric motortherein, conductor means for connecting the motor to the respectivecontacts on the tool section, an oscillating cutter mounted forwardly ofthe housing, a driving transmission means between the motor and thecutter, the housing having a debris conduit formed therein, the conduitcommencing near the cutter and terminating in a rearward opening in thehousing, the hose section having a forward opening formed therein andcommunicating with the rearward opening in the housing when the sectionsare joined together, means for substantially sealing the sectionsagainst air leakage therebetween adjacent to the communicating openings,a vacuum hose carried by the hose section and communicating with theopening therein, cable means carried by the vacuum hose and connected tothe respective contacts on the hose section, and switch means carried byone of the sections for selectively energizing the motor.
 3. A surgicalcast cutter, comprising a tool section and a complementary hose sectionrearwardly of the tool section, cooperating means for manually slidingthe sections relative to one another, releasable latching means forretaining the sections together, electrical contact means carried byeach of the sections and respectively engaging each other when thesections are joined together, the tool section having a housing, alow-voltage electric motor in the housing, conductor means connectingthe motor to the respective contacts on the tool section, an oscillatingcutter mounted forwardly of the housing, a driving transmission meansbetween the motor and the cutter, the housing having a debris conduitformed therein, the conduit commencing near the cutter and terminatingin a rearward opening in the housing, the hose section having a forwardopening formed therein and communicating with the rearward opening inthe housing when the sections are joined together, means forsubstantially sealing the sections against air leakage therebetweenadjacent to the communicating openings, a vacuum hose carried by thehose section and communicating with the opening therein, a low-voltagecable carried by the vacuum hose and connected to the respectivecontacts on the hose section, and switch means carried by one of thesections for selectively energizing the motor.
 4. In a surgical castcutter or other tool having a generally longitudinal axis, thecombination of a pair of axially-disposed mating sections releasablyjoined together, a first pair of diametrically-opposed parallel ribsformed on the rearward portion of one of the sections in a directionsubstantially at right angles to the longitudinal axis thereof, a secondpair of diametrically-opposed parallel ribs formed on the forwardportion of the other mating section, the respective pairs of ribs beingcomplementary to one another and slidably engaging each other as themating sections are brought together in a direction substantially atright angles to the longitudinal axis, each of the sections havingrespective housing side edges formed on an incline with respect to thecooperating pairs of ribs, the one section having a first debris openingformed therein, the other section having a complementary second openingformed therein, the openings each being inclined with respect to thecomplementary pairs of ribs, whereby, as the complementary ribs sliderelative to one another as the sections are brought together, therespective inclined side housing edges are brought into substantialabutting engagement with one another, and the inclined respectiveopenings in the sections become alined with one another withsubstantially no air leakage between the sections and around theopenings therein.
 5. In a surgical cast cutter or other tool having agenerally longitudinal axis, the combination of a pair of matingsections releasably joined together, a first rib means formed on therearward portion of one of the sections in a direction substantially atright angles to the longitudinal axis thereof, a second rib means formedon the forward portion of the other mating section, the respective ribmeans being complementary to one another and slidably engaging eachother as the mating sections are brought together in a directionsubstantially at right angles to the longitudinal axis, each of thesections having respective housing side edges formed on an incline withrespect to the complementary rib means, the one section having a firstdebris opening formed therein, the other section having a complementarysecond opening formed therein, the openings each being inclined withrespect to the complementary rib means, whereby, as the rib means sliderelative to one another as the sections are brought together, theinclined respective side housing edges are brought into substantialabutting engagement with one another, and the inclined respectiveopenings in the sections become alined with one another withsubstantially no air leakage between the sections and around theopenings therein, and respective electrical contact means carried byeach of the sections and engaging one another when the sections arefully joined together.
 6. In a surgical cast cutter having a generallylongitudinal axis, the combination of a pair of mating sectionsreleasably joined together, a first rib means formed on the rearwardportion of one of the sections, a second rib means formed on the forwardportion of the other mating section, the respective rib means beingcomplementary to one another and slidably engaging each other as themating sections are brought together in a direction transverse to thelongitudinal axis, each of the sections having respective housing sideedges formed on an incline with respect to the cooperating rib means,whereby, as the rib means slide relative to one another as the sectionsare brought together, the inclined side housing edges are brought intosubstantial abutting engagement with one another, one of the sectionshaving a downwardly-projecting transverse ridge formed therein, theother section having a transverse groove formed therein to receive theridge when the sections are fully brought together, thereby preventingan axial separation of the sections, and releasable latching means forretaining the sections in their fully joined position.
 7. In a surgicalcast cutter or other tool having a generally longitudinal axis, thecombination of a pair of mating sections releasably joined together, afirst rib means formed on the rearward portion of one of the sections, asecond rib means formed on the forward portion of the other matingsection, the respective rib means slidably engaging each other as themating sections are brought together in a direction substantiallytransverse to the longitudinal axis, each of the sections havingrespective housing side edges formed on an incline with respect to thecooperating rib means, whereby, as the rib means slide relatively to oneanother as the sections are brought together, the respective inclinedside housing edges are brought into substantial abutting engagement withone another, manually-manipulatable releasable latching means forretaining the sections in their fully joined position, and means carriedby one of the sections for disabling the releasable latching means andprecluding inadvertent actuation thereof and consequent undesiredseparation of the sections, said last-named means being intended to beactuated by an implement.
 8. A surgical cast cutter, comprising a toolsection having generally longitudinal axis, a complementary hose sectionreleasably secured to the tool section rearwardly thereof, a first ribmeans formed on the rearward portion of the tool section substantiallyat right angles to the longitudinal axis thereof, a second rib meansformed on the forward portion of the hose section, the respective ribmeans being complementary to one another and slidably engaging eachother as the sections are brought together in a direction substantiallyat right angles to the longitudinal axis of the tool section, the toolsection having a housing with a low-voltage electric motor therein, anoscillating cutter mounted forwardly of the housing, a drivingtransmission means between the motor and the cutter, the housing havinga debris conduit formed therein to one side of the motor and isolatedtherefrom, the conduit commencing near the cutter and terminating in arearward opening in the housing, the hose section having a complementaryforward opening formed therein, the openings being formed on an inclinewith respect to the complementary rib means, each of the sections havingrespective housing side edges formed on an incline with respect to thecomplementary rib means, whereby, as the rib means slide relative to oneanother in a direction substantially at right angles to the longitudinalaxis of the tool section, the inclined respective side housing edges arebrought into substantial abutting engagement with one another, and theinclined respective openings in the sections become alined with oneanother with substantially no air leakage between the sections andaround the opening therein, manually-manipulatable releasable latchingmeans for retaining the sections in their fully joined position, meanscarried by one of the sections for selectively disabling the latchingmeans and preventing inadvertent actuation thereof, electrical contactmeans carried by each of the sections and respectively engaging eachother when the sections are joined together, conductor means connectingthe motor to the respective contacts on the tool section, a vacuum hosecarried by the hose section and communicating with the opening therein,a low-voltage cable carried by the vacuum hose and connected to therespective contacts on the hose section, and switch means carried by oneof the sections for selectively energizing the motor.
 9. In a portablesurgical cast cutter, the combination of separable housing sectionsslidably engaging one another, manually-releasable latching means forretaining the sections in a fully joined position, a low-voltageelectric motor in one of the sections, the one section having a debrisconduit formed therein and isolated from the motor, the other sectionhaving an opening formed therein and communicating with the debrisconduit, a vacuum hose carried by the other section and communicatingwith the opening formed therein, a low-voltage cable means carried bythe vacuum hose, first electrical contact means carried by the othersection and connected to the cable means, and second electrical contactmeans carried by the one section and connected to the motor, the firstand second contact means engaging each other when the sections areslidably joined together.